Ironwood and its U.S. partner, Forest Laboratories, Inc., announced positive top‐line results in both of their confirmatory Phase 3 clinical trials assessing the efficacy and safety of linaclotide in patients with irritable bowel syndrome with constipation (IBS‐C). In both trials, linaclotide met all primary and secondary endpoints, including multiple endpoints assessing linaclotide’s effect on abdominal pain. Diarrhea was the most common adverse event in linaclotide-treated patients in these trials. The top-line results from these trials were consistent with the results from the previous clinical trials of linaclotide in patients with IBS-C and chronic constipation. For more detailed information on the top-line results from the Phase 3 IBS-C clinical trials, please refer to Ironwood and Forest’s joint press releases issued on September 13, 2010 and November 1, 2010; and for more information on the results from the Phase 3 chronic constipation clinical trials, please refer to Ironwood and Forest’s joint press release issued on May 3, 2010. Ironwood and Forest are targeting a New Drug Application (NDA) submission for linaclotide to the U.S. Food and Drug Administration (FDA) in the third quarter of calendar year 2011.

Ironwood and its European partner, Almirall, S.A., also announced positive top-line results from the above Phase 3 IBS-C clinical trials for the E.U. efficacy endpoints. For more detailed information, please refer to Ironwood and Almirall’s joint press releases issued on September 13, 2010 and November 1, 2010. Based on the positive top-line results, Almirall will make a one-time $20 million milestone payment, less applicable taxes, to Ironwood. Almirall is targeting a Market Authorization Application (MAA) submission for linaclotide to the European Medicines Agency (EMA) in the second half of 2011.

Ironwood’s Asian partner, Astellas Pharma Inc., recently dosed the first patient in its Phase 1, single-dose clinical study to assess the tolerability of linaclotide in healthy volunteers in Japan. Astellas anticipates completing the study in 2011.

Corporate

In September, Ironwood sold its interest in its subsidiary, Microbia, Inc., to DSM Holding Company USA, Inc. in exchange for cash proceeds of $9.5 million, payment of $1.1 million for Microbia’s remaining debt, and future contingent consideration based on the sale of products incorporating Microbia’s technology.

At the end of October, Ironwood was awarded four federal grants under the Qualifying Therapeutic Discovery Project program for linaclotide and Ironwood’s next three most-advanced clinical and pre-clinical candidates. Ironwood received the maximum grant for each of the four applications. This initiative was part of the Patient Protection and Affordable Care Act that was signed into law in March 2010.

Based on its current operating plan, Ironwood reaffirms its prior guidance that it anticipates ending fiscal year 2010 with greater than $220 million of cash, cash equivalents, and available-for-sale securities.